Triple action automobile body press



Dec. 4, 1945.

TRIPLE ACTION AUTOMOBILE BODY PRESS Filed June 24, 1940 4 Sheets-Sheet l PEI w. ERNST 2,390,359 I Dec.4, 1945. w. ERNST I V TRIPLE ACTION AUTOMOBILE BODY PRESS Filed June 24, 1940 4 Sheets-Sheet 2 .EEE

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l/wm MHTEITEI? T ATTOKIVIYS Dec. 4, 1945. v ERNST 2,390,359

TRIPLE ACTION AUTOMOBILE BODY PRESS Filed June 24, 1940 4 Sheets-Sheet s Patented Dec. 4, 1945 UNITED STATE s PATENT mm.

TRIPLE ACTION AUTOMOBILE BODY PRESS Walter Ernst, Mount Gilead, Ohio, assignor to The Hydraulic Development Corp. Inc., Wilmington, Del;, a corporation oi Delaware Application June 24, 1940, Serial No. 341,994

9 Claims. (Cl. 113-45) This invention relates to presses and, in particular, to multiple action presses.

Multiple action presses, as heretofore known,

' comprise a plurality of metal shaping punches one and the same die carrier-moves during subsequent shaping operations.

Another object of the invention consistsin the provision of a hydraulic multiple action press, in which; for shaping'the work piece in a plurality of steps, only one power unit is required, acting all the while through the same main ram.

It is still another object ofthe invention to provide a hydraulic multiple action press, inwhich the press bed is associated with hydraulically adjustable die gsupportingineans for holding the die associated therewith stationary during, subse quent shaping operations, while the press platen; movesinone and the same direction.

A still further object of the invention consists in the provision of a hydraulic multiple action press having a press bed and a pressing platen in whichthe press bed is associated with hydraulically adjustable die supporting means which is automatically adjusted responsive to a predetermined position of said pressing platen but held stationary during'subsequent shaping operations of said platen. a

It is a further object of the invention to provide a hydraulic multiple action press of the type set forth in the preceding paragraph, in which hydraulically adjustable die supporting means associated with the press bed works as die cushioning means between two subsequent actual shaping operations.

These and other objects and advantages of the Figure 4 is a diagrammatic illustration of the hydraulic system according to the invention.

Figures 5, 6 and '7 illustrate sequential steps during the work piece'shaping operation.

General arrangement The present invention comprises a press having a pressing platen associated with a first die member and a hydraulically adjustable bed plate for supporting a second die member. The bed plate is associatedwith a press bed, which comprises a stationary punch, and is held stationary during the shaping operation of the pressing platen so as to prevent operation of the stationary punch during the first shaping step; while bringing said stationary punch into action during the second working step.

Structural arrangement Referring to the drawings in detail, the pre s 1 tb'ii assiiiblie's, gne'rally' designated Ill and 20.

invention will appear more clearly from the following specification in connection with the accompanying drawings, in which:

Figure 1 illustrates a front view of the press according to the invention.

Figure '2 is a section along. the line 2-2 of Figure Figure 3 ill trates a section along the line 3-3 n i L f The pressheadalso supports clamping cylinderpiston assemblies 2| and 22 cooperating with the clamping platen 23. Supported by the press bed I l, which may be connected to the floor by screws 24, is a bed plate 25 which is hydraulicallyadjustable by means of cylinder-piston-assemblies, generally designated 26. While the pressing platen and clamping platen l1 and 23 respectlvely are guided in guides 21, the bed plate is guided by means of guides 28.

As willbeseen from Figure 2, the press illustrated in Figure 1 comprises eight clamping cylinders 29, associated with hollow clamping pistons 30, which are connected with the pressing platen I1. each clamping piston 30 is a cylinder 32, provided in the pressing platen [1. The clamping platen 23 is movable relative to the: pressing platen I1 and is supported thereby by means of a pluralit of rods 34 which pass through lugs 35 and 36 connected with the clamping platen 23 and the pressing platen I'I respectively and carry. at their ends nuts or collars 31 and 38. The pressing platen I1 is mrthermore connected with two auxiliary plungers 3B and 40 carrying 5 double-acting pistons 4| and 42. 'Arranged becommunicating with the bore 3| of valve 49 associated with the main cylinder 44.

The hydraulic system furthermore comprises cylinder relief and pump by-pass valves 58 and The surge valves 41, 48 and 49 and'the valves therein plungers I 88 connected with the bed plate 25. The press bed II furthermore comprises a plurality of push back cylinders I89 in which plungers II8 are reciprocablyv mounted, which plungers are likewise connected with the bed plate 25. The bedplate comprises a bore III adapted to receive a stationary punch II 2 (see Figure 5).

58 and U do not form a part of the present invention and for a more detailed description thereof reference may be had to U. S. Patent 2,193,248 to Ernst, issued March 12, 1940, and the Ernst patent application No. 286,063; filed July 24, 1939. The purpose of the surge valves 41, 48 and 49 is to preflll the adjacent cylinder portions of the cylinders 45, 45 and 44 at the beginning of the working stroke of the main pressing plunger 43, and in cooperation with the valves 58' and 5| to relieve the pressure in the upper portion of the cylinders 45, 48 and 44 for facili- .tating initiation of the platen I1.

retraction stroke of the The valve 58 isconnected with the main cylin- Each of the holding cylinders I81 is connected by a conduit II3 with a conduit II4, while each of the push back cylinders I89 is connected by means of a conduit II5 with a conduit II5. Branching of! from the conduit H4 is a conduit "1 comprisinga safety valve H8 and communicating by means of a conduit II9 with the fluid tank I4. The conduit 4 comprises two oppositely opening check valves I28 and -I2I and communicates on one hand with the upper portion of the auxiliary cylinder 45 and on the other hand with the upper portion of the auxiliary cylinder 45. The upper portion of the auxilder 44 by means of conduits 52 and 53, while the valve 5| is likewise connected with the main.

cylinder 44 by means of the conduits 54 and 55. Each of the conduits 53 and 55 has respectively associated therewith a safety valve 55 and 51. The surge valve 49 communicates, by means of a conduit. 58 and a conduit 59,-with the pumps I5 and I5. Also communicating with the conduit 59 are conduits 58 and 5| leading to the valve 58 and conduits 52 and 53 leading to the valve 5|. .The conduits 58 and 52 comprise respectively a safety valve 54 and 55. Furthermore, branch-- ing oil from the conduit 59 are conduits 55 and 51 provided with check valves 88 and 59 respectively. I P

A servomotor 18 pertaining to the variable delivery pump I5 communicates through a conduit 1| with'a two-way valve 12 adapted to efiect communication between a-conduit 13 and the tank I4 through an exhaust opening (not shown) in valve 12. Such servomotors in connection with variabledelivery pumps are well known in the art and for a more detailed description thereof reference may be had to U. S. Patent No. 2,184,665 to- Ernst. The conduit 13leads to the conduit 15 comprising check valves 15 and 11 opening in opposite directions, and communicates with each of the clamping cylinder bores 18 by conduits 19, 88, 8|, 82, 83 and 84. Each of the conduits 88, 8|, 82 and 83 comprises a check valve 85 opening toward the conduit 15.

Branching on from the conduits 19,- 88 and 8| are conduits 85, 81 and 88, each comprising a check valve 89 and leading respectively to relief valves 98. 9| and 92 associated with gauges 93, 94 and 95. The conduits 95, 91 and 98, branching of! from the conduits 82, 83 and 84 leadrespectively to safet valves 99, I88 and IIII associated with gauges I82, I83 and I84. The relief' valves 98, 9| and 92 and 99, I88 and IN are individually adjustable so as to open at a predetermined pressure through conduits I85, I85 to the fluid tank I4. In this way different clamping pressure may be obtained with the individual clamping cylinders 18.

The press bed I I comprises a plurality-of holding cylinders I81 having reciprocably mounted iary cylinders 45 and 45 communicates through conduits I22 and I23 with a conduit I24 leading to a two-way valve I25 which, in its turn, is

adapted to communicate through conduit I25 with the pump I5. The valve I25 is controllable by means of a control rod I21 which has adjustably connected therewith a collar I28 adapted to be engaged by the arm I29 connected with the pressing platen I1.

The conduits I22 and I23 are adapted respectively to communicate through the check valves I38 and I3I and conduits I32 and I33 with a con-' duit I 34 communicating with one side of the pumps I5 and I5. The other side of the pumps- I5 and I5 is connected with the conduit 59 which, in-its turn, communicates through conduits I35, 8 and I35 with the lower portion of the auxiliary cylinders and 48 respectively.

Branching ofl from the conduit H4 is a conduit I31 leading to a chamber I38 of a control I valve generally designated I 39. Arrangedin the chamber I380! the control valve I39 is a valve member I48 adapted to be actuated'by a control rod I4| adjustably connected with the arm I29 of the platen I1 by means of collars I5I and I52 which latter is continuously urged downwardly by a spring I59 engaging on one hand the platen I arm I29 and on the other hand the collar I52.

The valve member I48 is continuously urged upwardly by a spring I42 locatedv in the valve chamher I38 so as to interrupt. communication between the conduit I31 and the conduit I43 comprising a relief valve I44 and communicating with the conduit II 4. Downward movement of the valve member I48 by means of the control rod I 4| causes the conduits I31 and I43 to communicate with each other so that fluid below the plungers I88 may escape into the upper portion of the auxiliary cylinders 48 and 45.

Operation sponds to the end of the retraction stroke, the

pressing operation is carried out as follows:

The pumps I5 and I8 are started in any convenient manner by shifting the flow-control memher (not shown) associated therewith into full stroke forward position. flow-control member also causes fluid pressure to pass through the conduit 1I so as to cause the valve 12 to interrupt communication between the conduit 13 and the tank I4. While the pressing platen I1 together with the auxiliary pistons 4| and 42 will slide downwardly by gravity, the upper portions of the auxiliary cylinders 45 and 45 and of the main cylinder 44 will be supplied by fluid flowing from the tank I4 through the surge valves 41, 40 and 43. In addition thereto, the pumps I5 and I6 will supplythe main cylinder 44 with fluid through the conduits I34, 53 andv 55. Downward movement of the platen I1 also causes downward movement of the hollow clamping pistons 30, and the clamping cylinder bores 18 will be supplied with fluid flowing from the tank I4 through the check valves 33 and the conduits and 80 to 04. The clamping platen 23 supported by the pressing platen I1 will of course likewise move downwardly together with the platen I1. As soon as the clamping platen 23 engages the work piece I41, the clamping platen 23 comes to a standstill so that further downward movement of the pressing platen I1 causes a relativemovement of the plungers 33 with respect to the cylinders 32. This relative movement results in a building up of pressure in the cylinders 32 which pressure is conveyed into the cylinder bores 13 where it acts upon the hollow pistons thereby supporting the relative movement of the platen I1 and cylinders 32 with regard to the plungers 33 and increasing the clamping pressure exerted upon the clamping platen 23. If any excessive pressure should occur in the cylinders 32 and 18, this excessive pressure will be conveyed through the conduits 06, 81 and 88 and the conduits 36, 31 and 38 to the relief valves 30, 3I and 32, and valves 33, I00 and "II, which will then open to exhaust.

when the clamping platen 23 is thus firmly pressed against the work piece I41 the punches I45 and I45 begin to act upon the workpiece I41. .Pressure now builds up in the upper port on a of the main cylinder 44 and the auxiliary cyl inders 45 and 46 with the result that the surge valves 41, 48 and 43 and the check valves I30 and I3I close. At this time the platen arm I23 has engaged the collar I28 on the control rod I21 so as to efiect communication between the conduit I2Ii and the conduit I24, Pressure fluid will therefore also be supplied by the pumps I6 and I5 through the conduit I26, the valve I25, the conduit m and the conduits m and m to the auxiliary cylinders 45 and 46 respectively. The fluid expelled by the auxiliary pistons 4| and 42 is conveyed through the conduits I and I38 and the conduit 53 to the suction side of the pumps I5 I and I6. Since the fluid conveyed b the pistons H and 42 to the suction side of the pumps I5 and I5 is less than that required by the pressure side of said pumps, additional fluid is taken inirom thetank through the check valves 38 and 63 associated with the conduits 61 and 60 The shifting of the said in accordance with the shaping of the punches I and I43 and the corresponding recesses I43 and I in the lower die I48.

At the end of the first working step the control 7 I rod I4I engages the valve member I40 and, due to the further downward movement of the platen I1, moves the valve member I40 against the thrust of the spring I42- downwardly thereby establishing communication between the conduit I31 and the conduit I43. This position of the valvemember I40 enables the fluid in the holding cylinders I01 to escape through the conduits H3 and H4 into the auxiliary cylinders 48 and from there through the conduits I23 and I24 into the auxiliary cylinders 45, thereby supporting the fluid pressure acting upon the pistons 41| and 42 and the plunger 43, while the plungers I03 in cooperation with the cylinders I01 act as cushioning means and the bed plate 25 gradually recedes until it arrives at its lowermost position. As soon as this position has been reached, the stationary punch II2 has bulged out the work piece I41, as indicated in Figure '1, and the second shaping operation is finished.

As will bev seen from the drawings, the clamping platen or blank holder 23 does not firmly held in its position by the punches l45 and I46 pressing against the lower die and moves together with the pressing platen I1 and the bed. plate 20.

respectively. Since the pressure acting upon the pistons 4| and 42 also prevails in the conduit'II4 and since, furthermore, the valve member I40 is in its uppermost position, no fluid can'escape from the holding cylinders I01 so that the bed plate 25 is heldin its upper position. The pressing platen I1 now performs the, first work ng step, as indicated in Figure 6,'from which it will be noted that the work piece 141 has been shaped If, for any reason, the valve member I40 should get stuck or undue pressure in that portion of the conduit II4,'which is located between the check valves I20 and I2I, should develop for any other reason, the excess pressure will be released through the emergenc valve H8 and the conduit II3 leading to the fluid tank I4.

In order to start the retraction stroke of the pressing platen I1 to remove the work piece, the flow-control members of the pumps I5 and I5\ are shifted to full delivery retraction stroke position by any convenient means so that the condu t 53 becomes the pressure side and the conduit I34 becomes the suction side. As soon as this shifting movement is carried out. the cylinder relief and pump by-p'ass valves 50 and 5I release the pressure in the upper portion 01' the cylinders 44, 45 and 46, while thevalves I 30 and I3I open, thereby facilitating initiation of the retraction stroke. Pressure fluid from the pumps I5 and I6 now flows through the conduit 53' and the conduits I35 and I36 into the lower portion of the auxiliary cylinders 45 and 45', thereby moving the pistons M and 42 upwardly and lifting the pressing platen I1. At the same t me pressure fluid flows from the conduit I35 through t e conduits IIS and H5 into the lower portion ofthe push back cylinders I03, thereby lifting the-bed plate 25. The dimensions of the retrac- 1 tion side of the auxiliary pistons H and 42, with re ard to the diameter of the push back plungers IIO are preferably such that the platen I1 is lifted by means of the push back plungers H0.

The fluid expelled by the main pressing plunger 43 is exhausted through the now open surge valves 49 into the tank I4 and through conduits 53 and I34 to the suction side of the pumps l5 and I6.

During the first portion of the retraction stroke, the pressin platen l1 recedes, while the blank holder 23 still rests upon the work piece 1. As a result of this relative movement of the pressing platen I1 and the-blank holder 23, the space of the cylinders 32 above the upper surface of the plungers 33 gradually increases, while the space of the cylinders 18 above the upper surface of the hollow clamping pistons 30 decreases. Consef quently, the pressure tending to develop in the is conveyedthrough the conduit 14 to the valve 12 so as to effect communication between the conduit 13 and the tank I with the result that the fluid from the clamping cylinders 18 may freely exhaust through the conduits I5, 13 and valve 12 into the tank ll.

Retraction of the pressing platen I! will cause the control rod Ill to disengage the shifting member 0 so that the latter will again be lifted to its uppermost position by the spring I42, in which position communication between the conduits I31 and H3 is again interrupted.

After the auxiliary pistons ii and '42 and the mainpressing plunger 43 have performed the full retraction stroke, the pumps 15 and I6 are shifted to neutral or substantially no delivery position by any convenient means, well known to those skilled in the art, whereupon the press comes to a standstill. All parts now again occupy the position shown in Figure ,4 and the press is ready for another cycle.

Having thus fully described my invention what I claim as new and desire to secure by Letters Patent is:

1. In a multiple action press, a first die mem'- ber, fluid operable means for advancing and retracting said die member, a second die member for cooperating with said first die member to effeet a. first drawing-operation, a. movable support for said second die member, a fluid operable cylinder-piston-assembly for actuating said support, valve means operable to entrap the fluid, in said cylinder-piston-assembly for holding said assembly to pass to said fluid operable means and to assist the latter.

2. In combination in a multiple action press, fluid operable supporting means for movably supporting a first die member, a reciprocable press plunger adapted to support a second die member for cooperation with said first die member, a

third'die member stationarily mounted for exerting a shaping action on a work piece being shaped by said first and second die members, control means for hydraulically locking and temporarily maintaining said supporting means stationary in -a predetermined position to hold said work piece supporting means having a passageway therethough, means for locking and maintaining said supporting means in a predetermined position for cooperation with said die means to effect]; draw-' support stationary during said first drawing,

operation, a third die member arranged stationary for cooperation with said second die member, conduit means controlled by said valve means for establishing fluid connection between said cylinder-piston-assembly and said fluid operable means, and means responsive to a predetermined travel of said first die member for actuating said valve means to establish said fluid connection, thereby allowing movement of said movable support toward said third die member to enable a second drawing operation in response to a continued advance of said first die member while causing fluid expelled fromsaid cylinder-pistoning step, and means responsive to a predetermined advancement of said platen during said drawing step to unlock said supporting means for causing said platen, during its further advancing movement, to move said supporting means toward a stationary die member, thereby causing the latter to act upon said work piece through said pas-- sageway for exerting a on said work piece. E

4. In a multiple action press, a press head, a press platen associated with said press head and adapted to receive a first die member, a press 'bed, cushion means associated with said press bed and adapted to cooperate with said press platen, said cushion means being adapted to support a second die member and a work piece, hydraulically operable clamping means for clamping the work piece further shaping operation with respect to said'cushion means, a third die member stationary with respect to said bed and adapted to extend through said second die member, hydraulic motor means common to said press platen, said cushion means and said clamping means for operating the same, means for making said cushion means inefiective during a first shapirig action of said platen, and means operable in r sponse to a predetermined travel of said platen during said first shaping action to make said cushion means eilective while the platen continues its advancing movement for causing said third die member to extend through said second die member and to exert a shaping action upon said work piece. I I

5. In a multiple action press, a press plunger, hydraulic motor means operatively connected -with said pressplunger for reciprocating the same, a stationary die member, work piece supporting means movable with respect to said die member to selectivelyspace a work piece on said supporting means from said die member to allow said press plunger to exert a first shaping action on said work piece, or to bring said work piece into engagement with said die member, to cause the latter to exert a second shaping action on said work piece, a hydraulic cylinder-pistonassembly for movably supporting said supporting means, valve means normally entrapping the fluid in said hydraulic cylinder-piston-assembly to hold said supporting means stationary in spaced position from said die member, and-means responsive to a predetermined advancing movement of said press plunger to shift said valve means into position for effecting fluid connection between said cylinder-piston-assembly and said hydraulic motor means, thereby aiding the advancing movement of said press plunger and causing said die member to efiect said second shaping action.

6. In a multiple action press, a press platen, clamping means for clamping a work piece, hydraulic means for operating said clamping means and advancing and retracting said press platen,

said press platen being adapted to receive a first I die member, a press bed, a stationary die supported 'by said press bed, work piece supporting means movable-with respect to said press bed, fluid operable means for actuating said supporting means, valve means operable to entrap fluid finsaid fluid operable means to hold said work piece spaced from said stationary die and to allow'said first die memberto exert a first shaping action upon said work piece, and means responsive to a predetermined travel of said press platen for actuating said valve means to release fluid from said fluid operable means in response to the advancing movement of said supporting means together with said work piece toward said bed for bringing said work piece into engagement with said stationary die and causing the latter to exert a second shaping action upon said work piece. x 7. In a multiple action press, a reciprocable press platen adapted to receive a first die member, hydraulic motor means including a main cylinder and an auxiliary cylinder for advancing and retracting said platen, a pressbed, movable supporting means associated with said press bed for supporting a-work piece to be shaped, said supporting means being adapted to receive a second die member to exert a first shaping action upon said work piece, a third die member sta- .mined advancement of said platen to allow said tionary with respect to said press bed, a fluid operable cylinder-piston-assembly with said supporting means for movably supporting the latter; valve means normally enassociated der-piston-assembly and said auxiliary cylinder to .cause said supporting means to recede in response to the advancing'movement of said platen fluid operable advancing and retracting means for reciprocating said plunger, movable supporting means adapted to support a work piece and to cooperate with said first die for exerting a first shaping action upon said work piece, a fluid operable cylinder-piston-assembly for selectively effecting movement of said supporting means into advanced or retracted position, controlling means for controlling the release of fluid from said cylinder-piston-assembly, a fluid source for supplying actuating fluid to said press plunger and said cylinder-piston-assembly, means independent of said controlling means and responsive to the supply of fluid to said retracting means for conveying fluid to said cylinder-pistonassembly to move the same into advanced position, means continuously urging said controlling means into position for entrapping the fluid in said assembly, a second die stationarily mounted and adapted to exert a shaping action upon said work piece in response to a movement of said supporting means from its advanced position into its retracted position, and means responsive to a predetermined travel of said press plunger during said first shaping action for shifting said controlling means into releasing position to allow movement of said supporting means to its retracted position to make said second die efiective. 9. In a multiple action press, -a press platen, a shaping die'carried by said platen, movable supporting means adapted to support" a work piece and to cooperate with said platen, a, single hydraulic power unit for advancing and retracting said pla en and adjusting and holding said supporting means stationary during a predeterdle on the platen to effect a first shaping operation, oppositely extending stationary die means, and means responsive to a predetermined advancement during one and the same advancing stroke of said platen for causing said supporting means. to move concomitantly with said platen to bring said work piece into engagement with said stationary die means for efiecting a second shaping operation on said work piece.

WALTER ERNST. 

